During cell division,sometimes there will be failure of separation of sister chromatids. This event is called

Distinguish between cytokinesis and karyokinesis.

Identify the incorrect statement from the following.

The major phases of the cell cycle are:

Identify the correct statements: $(1)$ Synapsis occurs between homologous chromosomes during prophase $I$ of meiosis. $(2)$ Centromeres split during anaphase $I$ of meiosis. $(3)$ Spindle fibers completely disappear during telophase of mitosis. $(4)$ Nucleoli reappear during telophase $I$ of meiosis.

In which type of cell division does spindle formation not occur?